All drugs have the potential to interfere with your cancer treatment. This includes but is not limited to marijuana, hallucinogens, cocaine, amphetamines, opiates, anabolic steroids, inhalants, methamphetamine, and tobacco. If you have taken any drugs in the past or currently take drugs—even if it’s only every now and then—it is important that you tell your doctor or nurse. Not telling them is very risky. The drugs can change the chemistry of the cancer treatment and make it less effective or too toxic.
In addition to illegal drugs, you should not take prescription drugs or over-the-counter medicines (medicines you can buy at the store) during your treatment unless your doctor has approved the medication and the dosage. Using unapproved drugs or medications can decrease the success of your treatment and make it more difficult for you to beat cancer. Plus, when you take illegal or prescription drugs purchased “off the streets” you never really know what you are putting into your body.